Alarm clock



March 18, 1941. JUNGHANS 2,235,580

ALARM CLOCK Filed June 9, 1937 2 Sheets-Sheet 1 Ir v8 vz for:

H. JUNGHANS ALARM CLOCK March 18, 1941.

Filed June 9, 1937 2 Sheets-Sheet 2 I1? verz for: He Z uz Jury Patented Mar. 18, 1941 UNITED STATES PATENT canoe Application June a, 1937, serial No. 141,345 m a May 2, use

3 Claims. (CI. 58-16) The invention deals with an alarm mechanism in which the alarm shutting off lever or button is automatically released upon winding up of the alarm spring.

The present invention relates to alarm clocks having means for stopping the alarm during or before the time for which the alarm is set for action, and more particularly to devices of that kind in which the stopping member is in interlocking connection with the locking means.

As well known, devices for stopping the alarm before the set time are provided because a person very frequently awakens of his own accord shortly prior to the time when the alarm is due to function and does not wish to be disturbed by the noise of the alarm. The alarm can then be rendered inoperable, so that it will not be able to function at the time for which it was ori inally set.

The essence of the device according to the invention consists in the fact that the requisite premure for maintaining the interlocking connection is derived from the escapement wheel, and through the medium of the stoppin device the alarm operating mechanism is moved back, in opposition to the alarm operating spring, out of the locked position governed by the alarm locking spring, to such extent until the stopping device interlocks with the locking device.

Various methods may be adopted in the structural embodiment of this general idea according to the invention. Thus, for example, according to one feature of the invention, the hammer shaft may be furnished, not only with the usual locking arm, but also with an additional arm, which co operates in such fashion with the usual locking lever directly engaging with the escapement wheel that upon depression of the stopping memher before the set time the locking lever presses against the said additional arm, thereby lifts the pallet lever in opposition to its tension by reason 'of the escapement wheel out of the teeth, and then engages with the teeth itself by means of its end portion and is firmly held by the pressure of the teeth of the escapement wheel. Or in accordance with an additional feature of the invention the pawl for intercepting the stopping memarrangement may be such in accordance with the invention that the usual locking arm co-operating with the alarm locking spring is extended in such fashion that it passes to within reach of the stopping member stem furnished with an undercut conical point and is bent of! transversely to the axis thereof and in such fashion towards the stem that it is capable of interlocking with the same in the two extreme positions determined by the position of the locking arm in relation to the alarm locking spring.

Certain embodiments of alarm stopping means in accordance with the invention are illustrated in the accompanying drawings.

Figs. 1 to 4 show a form of embodiment in which the stopping member is interlocked with .the escapement wheel.

Figs. 5 to 8 show a second embodiment in which the stopping member is interlocked with the pallet lever shaft.

Figs. 9 to 12 show a device for limiting the unwinding of the alarm spring, capable of being employed in the case of stopping means accordins to Fi s. 1 to 8.

Fig. 1 is a front view of the stopping means according to the first form of embodiment in the position of release, the alarm device being locked by the alarm locking spring.

Fig. 2 is a front view of the device in the locked position after it has been actuated outside of the time when it is due tofunction.

Figs. 3 and 4 are plan and elevatlonal views corresponding to Fig. 2 (locked position).

Fig. 5 is a front view of the second form of embodiment, also in the position of release, wherein the alarm device is locked by the alarm look ing spring.

Fig. 6 is a corresponding view in the locked position after the device has been rendered inoperable outside of the time when it is set to function.

Figs. '7 and 8 are plan and elevational views corresponding to Fig. 6 (locked position).

Fig. 9 is a front view of a device for limiting the unwinding of the alarm spring as applied to a stopping device according to Figs. 5 to 8. The stopping device is in the position of release, but the alarm device is locked by the alarm locking spring.

Fig. 10 is a similar front view showing the device in the locked position.

Figs. 11 and 12 are plan and elevational views respectively corresponding to Fig. 10.

In the first embodiment (Figs. 1 to 4) the stopping lever is designated a. It is mounted to rock at c between the plates d, d. It is actuated 1 by the upwardly and downwardly movable stop- The projection a2 co-operates with an arm h on the pallet lever shaft 9', which arm is curvedin hook-like fashion at its free end. The pallet lever shaft g carries the usual stopping arm 94, which co-operates with the alarm locking spring s.

The object and the embodiment of the alarm locking spring in the case of an alarm clock are well known to those skilled in the art; it need merely be mentioned by way of explanation that the same is controlled by the wheel-work of the clock. The control is efiectedby means of a gear wheel t which carries a cam ti and at the set time the gear wheel is shifted axially and moves the locking spring out of reach of the stopping arm 94. The said gear wheel is moved continuously by the wheel-work, and by means of the cam the alarm locking spring is gradually again flexed to within reach of the stopping arm. The time necessary for this purpose amounts to 1 to 2 hours, and it is clear that in alarm clocks of the usual kind the alarm spring cannot be rewound during this time, as the alarm would again immedately run down. Y

The operation of the stopping device is as follows:

1. Stopping after the settime.

The stopping lever a is depressed by means of the stopping button 17 until the projection at engages between the teeth of the locking wheel. The locking lever is curved in such fashion that under the pressure of the teeth of the escapement wheel I the latter and the locking arm interlock. The function just described is known per se. Novelty, however, is constituted by the following:

2. Stopping before the set time.

In this condition the stopping arm 94 bears against the end of the alarm locking spring 8. The escapement wheel f is accordingly at rest, and upon depression of the lever it its projection al, although caused to engage between the teeth of the escapement wheel I, would not find any hold if the arm in were not provided on the shaft 9. This arm is so arranged that the lever a when pressed downwards first strikes with its projection (12 against the hook-like end i of the arm h. Upon additional downward movement of the lever a the lever 72. yields, there being rotated simultaneously the shaft 9 and, by way of the alarm pallet lever l, the escapement wheel. The arm I; is so arranged that the alarm escapement wheel is turned back in opposition to its normal direction of movement, viz., by an are which is greater than one-half of the spacing between the teeth. This return movement must also be completed before the projection al comes within reach of the teeth of the escapement wheel. When the return movement has taken place the projectiona2 also slides over the hook-like end i of the arm I). and the projection al enters simultaneously' into a gap in the teeth of the escapement wheel. Since during this sliding action the escapement wheel has also been released it attempts to run down. It is, however, prevented from doing this immediately a tooth of the escapement wheel meets against the projection al The escapement wheel and the locking arm are now again interlocked as in the case of the stopping action after the set time and as described in the foregoing. Also in this case it is the pressure of the teeth of the escapement wheel caused by the alarm operating spring which maintains the interlocking action.

In the second embodiment (Figs. 5 to 8) the parts agreeing in function with those set out in the first embodiment have been furnished with similar reference characters. There is provided a stopping lever p with the edge pl. The leverp is rotatably mounted at 102 between the plates d, d, and a spring e presses the lever p upwards. For actuation of the lever there is provided the stopping button b, the guide b3 for which is carried by the clock casing is. There are also provided the usual alarm anchor shaft 9 with the pallet lever Z and the stopping arm g4, which cooperates with the alarm locking spring 8. The escapement wheel is designated The shaft 9 supports the pawl gl which latter has a bevel or cam 92 and adjacent thereto a recess 93.

The operation of the stopping device is as follows:

g l. Stopping after the set time.

The pawl *gi rocks backwards and forwards together with the anchor shaft. If now the lever p is pressed downwards by means of the stopping button, either the pawl gl engages immediately by means of its recess g3 with the edge pl when the pawl moves from the left to the right, or the edge abuts against the bevelled portion g2 and the pawl is moved to such extent from the right to the left that the edge is able to enter the recess 3. The interlocking action is maintained by the force of the main alarm spring acting on the shaft :9. v

2. Stopping before the set time.

As shown in'Fig. 5, the edge pl of the lever p abuts upon the downward movement of the latter against the cam or bevel g2. The pressure exerted by the hand on the stopping button 12 causes the pawl to yield until the edge pl drops into the recess 3. The entire alarm operating mechanism is thereby moved slightly backwards as compared with its normal direction of movement, 1. e., the main alarm spring is slightly wound, and again relaxes when the edge pl enters the recess 93. It will be clear that here again it is the force of the alarm operating spring, the pressure of which is utilised for maintaining the interlocking of the lever 31 and the pawl gl.

A4 device representing an advantageous addition to the embodiments according to Figs. 1 to 4 or 5 to 8 is shown in Figs. 9 to 12. If an alarm clock fitted with these stopping means is allowed to function until the main alarm spring has completely run down, no force will act ultimately on the alarm anchor and the latter is capable of assuming any desired position, When the wheel movement again slowly retm'ns the alarm locking spring into the locking position it may occur that the stopping arm g4 comes to rest below the point of the alarm locking spring instead of over the same. It will be quite clear from Figs. 1 to 4 and 5 to 8 that when the alarm is stopped before the set time the point of the locking spring s is bent forcibly upwards. Now it is certainly possible to construct the locking spring so that it is capable of withstanding this load. A better solution, however, is that shown in Figs. 9 to 12.-

The embodiment of the alarm mechanism corresponds in all parts to that shown in Figs 5 to 8 and described in the foregoing with the exception of the part designated gi therein. This is constructed in the form of a device m usually referred to as an unwinding lock. It is employed in order during a certain state of unwinding of the main alarm spring to hold the alarm anchor shaft, so that the anchor forms a locking means with respect to the alarm escapement wheel. In this manner a complete relaxation of the main alarm spring is avoided.

In the present case the arrangement of the unwinding lock m serves an additional purpose. As well known, the convolutions of the alarm spring n are permitted to move outwards (in Fig. 10 towards the left). The unwinding lock or projects into the path of this outward movement. When now the convolutions have moved outwards to a certain extent the outermost one moves against the arm m and prevents the anchor shaft, which at this moment (in the drawing) is moving clockwise as seen in Fig. 10, from additionally oscillating, i, e., prevents the pallet lever from leaving the escapement wheel. It will be clear that this locking action always takes place when the anchor is just in front of the stopping position, i. e., when the pawl gl is just in front of its extreme position towards the left. In consequence, upon the stopping of the alarm device by the unwinding lock 11:, the stopping arm g4 is always situated above the locking spring 3. If a stopping is made before the set time, the arm at lying above the spring s can freely lift therefrom. Preferably upon the provision of a pawl according to Figs. 5 to 8 the unwinding lock m is made to be integral with the pawl and bent. In the stopping device according to Figs. 1 to 4 the un winding lock would be required to be made as usual as a separate part, for example bent from wire and secured to the anchor shaft.

The release of the alarm stopping device in all of the embodiments described takes place in the known fashion by a slight winding action imparted to the main alarm spring. This action is imparted to the alarm escapement wheel and also to the anchor shaft.

It will be understood that no limitation is made to the specific form of embodiment shown in the drawings, and that numerous modifications are quite possible within the meaning of the above description and the annexed claims without departing from the spirit of the invention.

Having now particularly described and ascertained the nature of my said invention, and in what manner the same is to be performed, I declare that what I claim is:

1. In an alarm clock, a clock movement frame, an alarm escapement wheel with co-operating pallet lever, an alarm spring, means for setting the alarm to function at a desired time, a stop- Ding device for stopping the alarm at any time, a shaft carrying an alarm hammer and the pallet lever, a pawl mounted on the said shaft and having a bevelled surface and an adjacent recess, and a locking lever carried by the said clock movement frame and adapted upon actuation of the said stopping device to engage with the said pawl into a hook-like connection by turning back first the said pallet lever against the force of the alarm spring by means of the bevelled surface on the said pawl until the engaging end of the said stopping lever enters the said recess.

2. In an alarm clock, a clock movement frame, an alarm escapement wheel with co-operating pallet lever, an alarm spring, means for setting the alarm to function at a desired time, a stopping device for stopping the alarm at any time, a shaft carrying an alarm hammer and the pallet lever, a pawl mounted on the said shaft and having a bevelled surface and an adjacent recess, a locking lever carried by the said clock movement frame and adapted upon actuation of the said stopping device to engage with the said pawl into a hook-like connection by turning back first the said pallet lever against the force of the alarm spring by means of the bevelled surface on the said pawl until the engaging end of the said stopping lever enters the said recess, and means tion of the said stopping device to engage with the said pawl into a connection by turning back first the said pallet lever against the force of the alarm spring by means of the bevelled surface on the said pawl until the engaging end of the said stopping lever enters the said recess.

HELMUT JUNGHANS. 

